Practice bomb



July 18, 1944. H. w. MITCHELL PRACTICE BOMB F iled Oct. 22, 1942 2 Sheets-Sheet l FIGL.

INVENTOR. HARRY W. MITCHELL BY f 4; z/ mww ATTORNEYS,

y 1944- H. w. MITCHELL 2,354,039

PRACTICE BOMB Filed Oct. 22, 1942 2 Sheets-Sheet 2 INVENTOR. HARRY W. MITCHELL ATTORNEYS.

Patented July 18, 1944 UNITED STATES PATENT OFFICE .PRACTICE'BOMB Harry'WLMitchell, Shaker Heights, Ohio Application etober22, 1942, Serial No. 462,978

8 Claims.

This invention relates,-as indicated, to practice bombs, *but has reference more particularly to practice bombs which simulate, in appearance, these-called demolition bombs.

"It has heretofore been customary in bomb practice, to use sheet metal containers, simulating in generalappearance and in certain of its characteristics, an actual bomb, but filled, for military use, withsand, and for naval use, with saltwater. These practice bombs are, in most instances, made from a number of sheet-metal parts welded or riveted together, requiring skilled labor for their assembly and manufacture into complete units. Moreover, after use, the bombs had to be salvaged so that additional labor had to be employed to recover and salvage them. Aside from this, the growing shortage of strategic materials, such as steel, has created a problem as to whether or not practice bombs in quantities sufficient to properly train bombardiers can be made available for the successful prosecution of the war.

With those disadvantages and prospects in mind, I have developed a practice bomb which is made of readily available non-strategic materials, which can be manufactured so inexpensively as to .not require that .it be salvaged, and which can be readily manufactured and assembled by untrained and unskilled laborers, utilizing inexpensive and readily available equipment or machinery.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings, forming a part of this specification, and in which like numerals are employed to designate like parts throughout the same,

Fig. 1 is an elevation of a practice bomb embodying my invention;

Fig. 2 is an enlarged cross-sectional View, taken on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged cross-sectional view, taken on the line 3-3 of Fig. 1, and

Fig. 4 is a bottom plan view of the bomb.

In the drawings, wherein for the purpose of illustration, is shown a preferred embodiment of my invention, the numeral I designates the body of the practice bomb, which is in the form of a cylinder, preferably formed from spirally-wound cardboard stock, about A; of an inch in thickness, and having adhesively secured to its exterior a cover 2 of heavy kraft paper, which serves to conceal the joints and renders the body impervious to the flow of sand or water. This imperviousness may be further insured by a coating or impregnation of the body by means of a suitable lacquer or other water-impervious material.

The body I has adhesively secured to the in terior surface thereof a ferrule 3 which is likewise made of cardboard and extends into the body I approximately three inches and beyond said body approximately one inch. To the portion of the ferrule 3 which projects beyond the body I, there is secured a nose 4, of conventional shape, but preferably formed from an acetate plastic which can be conveniently cast to have a uniform thickness of about of an inch, the use of such a plastic enabling the nos to have a desired smooth "outer surface, unbroken by cracks or blemishes which might affect the course of the bomb.

The use .of the ferrule 3 further enables the nose to form abutt joint With the body l, which is highly desirable. The nose is secured to the ferrule byimeans of a series of circumferentiallyspaced rivets 5, which are preferably T e" diame ter and of the star clinchitype.

Secured to the opposite end of the body I, as by means of star clinch rivets 6, is a head consisting of a conical portionl, a flange 8, to which the body I is riveted and a flange or collar 9 of smaller diameter than the flange 8. This head is also preferably in the form of a casting approximately of an inch thick, of an acetate plastic similar to that from which the nose is formed.

Secured to the flange 9 of the head, as by means of rivets 20, is a metallic collar 2|, having a rebent smoothly rounded flange 22 which extends for a short distance into the head. This collar 2| serves for the attachment of a metallic cover 23, which may be readily removed.

It will be noted that the flange 8 extends into the body I, but that about half of this flange extends out of the body I. This enables a cone II) to be fitted over the flange and to be easily and quickly aligned with the body. The cone Ill has a flange H which forms a butt joint with the body and is riveted to the flange 8 by means of star clinch rivets l2, which are preferably in staggered relation with the rivets B.

The cone I0 is preferably formed from vulcanized fiber or a special paper board stock, approximately e" thick, and serves to centralize a filler sleeve l3 made of paper stock similar in nature and thickness to that from which the body I is made. The sleeve I3 is in alignment with the head and fits over the collar 2!, the

sleeve being secured to the collar and flange 9 of the head by means of the rivets 20.

The sleeve I3 is provided at its outer end with a paper cap M which has a press fit with the sleeve, and which may be easily removed to permit filling of the bomb with sand or water.

The bomb further includes fins l5, of conventional form, but preferably made of a special paper board stock, approximately thick, the fins being provided with suitable flanges whereby they are secured; as by means of star clinch rivets 16, to'the cone and to the sleeve l3.

The practice bomb is provided with the usual suspension lugs H, which extend throughthe body of the bomb, and are maintained in position by' means of nuts [8, the body being reinforced at the points through which the lugs extend by I means of reinforcing strips 19 and 20 of sheet metal. These strips, the lugs, nuts and rivets therefore constitute the only portions ofv the bomb which are metallic. I

After the bomb has been assembled in the man ner described, itmay be dipped in a paint or I pounds which the ordinary sheetmetal practice bombs weigh. In order .to make up the difference in weight, in making a 100 pound demolition practice bomb, an additional ten'pounds of sand will therefore be introduced into the bomb of: the present invention, sufficient additionalspace within the body or sleeve being. usually providedffor this purpose. v It follows from the'foregoing description that I have provided a practice bomb which is made from non-strategic, readily available materials, which can be readily manufactured and'assembled atminimum cost andby the use of unskilled labor, utilizing inexpensive and readily available equipment or machinery, and which can be made so inexpensively as not to require that it be salvaged. In its unfilled condition, moreover, itis so light thatit can be;handled with little effort.-

Itis to be understood that the form of my in-' vention,'herewith shown and described, is to'be taken as a'preferred example of the same,'andthat various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my invention, or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. A practice bomb comprising a body formed of paper stock and a nose formed of a plastic, said nose having a smooth outer surface unbroken by cracks or blemishes which might affect the course of the bomb.

2. A practice bomb comprising a body and cone formed of paper stock, andanose formed of a plastic," said nose having a smooth outer surface unbroken by cracks or blemishes which might affeet the course of the bomb.

,3. A practice bomb comprising a body and formed of paper stock, and a nose and head formed ofa plastic, said nose having a smooth outer surface unbroken by cracks or blemishes which might affect the course of the bomb.

4. A practice bomb comprising a body, cone and fins formed of paper stock, and a nose and head formed of a plastic, said nose having. a smooth outer surface unbroken by cracks or blemishes which might affect the course of the bomb.

5. A practice bomb comprising a body formed of paper stock and a nose formed of an acetate plastic, said nose having a smooth outer surface unbroken by cracks or blemishes which might affect the course of the bomb.

6.'A practice bomb comprising a body, a cone and a head, said head having a flange extending from a point within said cone to a point within said body, said body and cone being connected to said flange.

7. Apractice bomb comprising a body, a cone and a head, said head having a conical bodyv and a flange integral with said body,said flange extending from a point within said cone to a point within said body, said flange interconnecting and permanentlysecured to said body and cone.

8. A practice bomb comprising a body and cone of paper stock, a sleeve of paper stock extending from a point within said cone to a point below said cone, a head connected to said sleeve and having a flange extending from a pointr within said cone to a point within said body, said flange connected to said body and cone, and fins of paper stock riveted to both the cone and the portion of the sleeve whichextends below said cone.

I HARRY, w. MITCHELL}.

cone 

